1. Field of the Invention
The invention relates to a device for recording a digital information signal in an information track of a record carrier, comprising:
an input terminal for receiving the digital information signal, PA0 an encoding device having an input coupled to the input terminal and having an output, which encoding device comprises an aT precoder, where a is an integer greater than or equal to 1 and T is the bit period of the signal, and,
a recording device having an input coupled to the output of the encoding device, for recording the encoded digital information signal in the information track on the record carrier.
2. Description of the Related Art
A device of this type is known, for example, from European Patent Application No. 339,724 encoding in such device is described according to which an n-bit information word is converted into an (n+m)-bit channel word by using a look-up table, subsequent to which the channel word is applied by a 2T precoder to a recording device for recording the thus encoded (n+m)-bit channel word on a magnetic record carrier. More specifically, an 8-to-10 bit conversion is described in which for each 8-bit information word no less than three 10-bit words from the aforementioned table are available having mutually different disparities.
With an appropriate selection from these three 10-bit words the digital sum value of the serial data stream of the channel word at the output of the precoder can be controlled in such a way that a desired variation of the digital sum value as a function of time is realised.
The above publication a pilot signal is thus accommodated in the serial data stream and which when reproduced from the record carrier may, for example, be used to control tracking.